package com.dhkj.web.utils;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class ZipUtils {

    /**
     * 使用gzip进行压缩
     */
    public static String gzip(String primStr) {
        if (primStr == null || primStr.length() == 0) {
            return primStr;
        }

        ByteArrayOutputStream out = new ByteArrayOutputStream();

        GZIPOutputStream gzip = null;
        try {
            gzip = new GZIPOutputStream(out);
            gzip.write(primStr.getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (gzip != null) {
                try {
                    gzip.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return new BASE64Encoder().encode(out.toByteArray());
    }
//
//    /**
//     * <p>Description:使用gzip进行解压缩</p>
//     *
//     * @param compressedStr
//     * @return
//     */
    public static String gunzip(String compressedStr) {
        if (compressedStr == null) {
            return null;
        }

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        ByteArrayInputStream in = null;
        GZIPInputStream ginzip = null;
        byte[] compressed = null;
        String decompressed = null;
        try {
            compressed = new  BASE64Decoder().decodeBuffer(compressedStr);
            in = new ByteArrayInputStream(compressed);
            ginzip = new GZIPInputStream(in);

            byte[] buffer = new byte[1024];
            int offset = -1;
            while ((offset = ginzip.read(buffer)) != -1) {
                out.write(buffer, 0, offset);
            }
            decompressed = out.toString();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (ginzip != null) {
                try {
                    ginzip.close();
                } catch (IOException e) {
                }
            }
            if (in != null) {
                try {
                    in.close();
                } catch (IOException e) {
                }
            }
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                }
            }
        }

        return decompressed;
    }
//
//    /**
//     * 使用zip进行压缩
//     *
//     * @param str 压缩前的文本
//     * @return 返回压缩后的文本
//     */
//    public static final String zip(String str) {
//        if (str == null)
//            return null;
//        byte[] compressed;
//        ByteArrayOutputStream out = null;
//        ZipOutputStream zout = null;
//        String compressedStr = null;
//        try {
//            out = new ByteArrayOutputStream();
//            zout = new ZipOutputStream(out);
//            zout.putNextEntry(new ZipEntry("0"));
//            zout.write(str.getBytes());
//            zout.closeEntry();
//            compressed = out.toByteArray();
//            compressedStr = new BASE64Encoder().encodeBuffer(compressed);
//        } catch (IOException e) {
//            compressed = null;
//        } finally {
//            if (zout != null) {
//                try {
//                    zout.close();
//                } catch (IOException e) {
//                }
//            }
//            if (out != null) {
//                try {
//                    out.close();
//                } catch (IOException e) {
//                }
//            }
//        }
//        return compressedStr;
//    }
//
//    /**
//     * 使用zip进行解压缩
//     *
//     * @param compressedStr 压缩后的文本
//     * @return 解压后的字符串
//     */
    public static String unzip(String compressedStr) {
        if (compressedStr == null) {
            return null;
        }

        ByteArrayOutputStream out = null;
        ByteArrayInputStream in = null;
        ZipInputStream zin = null;
        String decompressed = null;
        try {
            byte[] compressed = new BASE64Decoder().decodeBuffer(compressedStr);
            out = new ByteArrayOutputStream();
            in = new ByteArrayInputStream(compressed);
            zin = new ZipInputStream(in);
            zin.getNextEntry();
            byte[] buffer = new byte[1024];
            int offset = -1;
            while ((offset = zin.read(buffer)) != -1) {
                out.write(buffer, 0, offset);
            }
            decompressed = out.toString();
        } catch (IOException e) {
            decompressed = null;
        } finally {
            if (zin != null) {
                try {
                    zin.close();
                } catch (IOException e) {
                }
            }
            if (in != null) {
                try {
                    in.close();
                } catch (IOException e) {
                }
            }
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                }
            }
        }
        return decompressed;
    }


}